This invention relates to cover systems. More particularly, this invention relates to cover systems for scientific instruments, e.g. spectrometers.
Many scientific instruments (e.g. spectrometers) include a compartment or location where a sample to be analyzed must be placed for testing. When the testing involves the use of light, it is necessary to close the compartment to prevent stray light from interfering with the testing.
A variety of hinged and sliding covers have been previously used in a variety of instruments. None of such covers, however, have exhibited the features and advantages provided by the present invention.
In accordance with the present invention there is provided an instrument housing which includes a sample compartment and a sliding cover system for enclosing the compartment. The sliding cover system is especially useful in instruments involving optical measurements of samples (e.g. spectrometers).
In one embodiment, the system comprises:
(a) cover means including an elongated slot or raceway;
(b) a post member secured to the instrument housing;
wherein the raceway of the cover means is adapted to engage the post member.
The upper surface of the instrument housing also preferably includes a recess for receiving the cover means and guiding the cover between open and closed positions. Alternatively, the cover could be guided by mating slots and ribs in the upper surface of the housing and the lower surface of the cover (e.g. there could be one or more slots in the lower surface of the cover and one or more protruding ribs or raised features in the upper surface of the housing, or vice-versa).
Preferably the cover is arcuate shaped, and the upper surface of the instrument housing is also arcuate shaped so that the cover slides in a radial fashion on the mating surface of the housing. Gravity also assists in the movement of the cover between open and closed positions as the mass of the cover passes over the center of gravity. Gravity also provides the force to hold the cover in its fully open or fully closed positions.
No fasteners are visible in the attachment of the cover to the housing. The cover can be removed by the user without the use of tools. This results in ease of cleaning of the housing and the recess where the cover resides.
In the open position, the cover remains attached to its mating housing and is not obtrusive. The cylindrical or spherical shape of the cover also provides closure over a peak point, allowing a high clearance while at the same time providing a lower access height when the cover is in the open position.
The cover is the uppermost part of the instrument, which makes it easy for a user to move the cover to its open position even while holding samples or other items.
The radial or spherical shape interface between the sliding cover and the mating support surface of the instrument housing provides for a theoretical pivot point outside of the instrument""s physical envelope.